+atk -def Fallen Robin build

It really depends on what skills you can give him, but he’s going to have the highest base attack in the game and still have good defenses.
So i’d keep his base kit, but give him draconic aura as a special, if you have access to it close defence or distant defence for his a slot OR, fury 3 for a cheaper option. Keep the rest of his skills (unless you run him in an armour team, in which case give him hone or fortify armour) and he’s good to go!

Brazen Def/Res
Vengeful Fighter
Threaten Atk
Draconic Aura
Pivot
And DD / CD SS

TBH, having played him everyday since his release, I think the only stats that matters is his attack, as long as you have him with an attack boon and equip him with Bold Fighter 3 you are all set.
He's a good enemy phase unit,but Hector,Myrrh and Hardin all play this role better than him, he truly shines when he moves to player phase,basically slaughter everything he faces regardless the unit color.